Hermetic sealing of an enclosure is often desired to maintain a contaminant-free or low contaminant environment. A contaminant-free or low contaminant environment may be necessary for operation of particular devices. That is, contamination within a hermetic enclosure or package can lead to premature failure of the various enclosed components.
Corrosive effects due to the presence of oxygen, moisture, and other oxygen releasing species can pose a problem in microelectronic circuitry. Wire bonding of microelectronic components to the packaging may involve the use of aluminum within the wire bonds. Oxidation of the aluminum wire pads due to the presence of oxygen leads to the corrosion of the wire pads. For example, in the presence of moisture, the oxidation reaction of aluminum can proceed until the exposed aluminum is completely reacted or corroded. Such oxidation can ultimately lead to the failure of the microelectronic component. As such, it is desirable to reduce the presence of oxygen, moisture, or other oxygen releasing species in a hermetic enclosure.
In addition, potential corrosive effects may occur due to the presence of other damaging elements. For example, active device functions can be deleteriously affected by the presence of hydrogen. Water in the presence of sodium can supply hydrogen atoms which diffuse through the passivating layer(s) of a semiconductor affecting the performance of the semiconductor component. Component failure may be due to increased leakage currents, failure of field emission transistors (FETs) to enhance or deplete properly, etc.
One solution is to provide a getter material to remove and sequester contaminants (e.g., oxygen, moisture, or other oxygen releasing species, etc.) within a hermetic enclosure. Such gettering is conventionally performed by globally elevating the hermetic enclosure beyond a threshold temperature necessary to initiate a gettering reaction. However, elevating the entire hermetic enclosure may unnecessarily and deleteriously affect the circuitry of the components contained within the hermetic enclosure.
Thus, a need exists for an apparatus and method for sequestering a contaminant within a hermetic enclosure without damaging circuitry within the hermetic enclosure. A further need exists for an apparatus and method which meets the above need and prevents corrosion due to oxidation within the hermetic enclosure. Another need exists for an apparatus and method which meets the above needs and which provides for the lifetime extension of the enclosed components.